The flanger’s DEL parameter sets the base delay time, which puts a comb filter on the signal — evenly spaced notches at odd multiples of 1/(2τ), where τ is the delay. With DEP at zero (LFO off, static comb), that comb has a clear fundamental “note” to it and high (negative or positive) feedback levels, and it turns out DEL can be tuned like an oscillator.
Rough approach: I filtered white noise through the flanger, DEL swept while reading notch position off an FFT/spectrum display, gave a first-pass calibration — good enough to land in the right octave. From there, each pitch was dialed in against a tuner, using DEL for the coarse note and FINE for the cent-level correction (FINE runs 0–127, effectively adding FINE/128 on top of the DEL step — using my typical trick with LFO Designer’s flat-waveform fine control).
τ(DEL, FINE) ≈ 0.0874 × (DEL + FINE/128) + 0.107 ms, fit from four ear-tuned reference points spanning C2–C5. Table below covers F#1 up to E7, the practical range of the parameter — above E7, DEL sits at 0 and only FINE is doing the work, which is the resolution ceiling.
| Note | Freq (Hz) | DEL | FINE |
|---|---|---|---|
| F#1 | 46.25 | 122 | 52 |
| G1 | 49.00 | 115 | 60 |
| G#1 | 51.91 | 108 | 117 |
| A1 | 55.00 | 102 | 94 |
| A#1 | 58.27 | 96 | 115 |
| B1 | 61.74 | 91 | 50 |
| C2 | 65.41 | 86 | 25 |
| C#2 | 69.30 | 81 | 37 |
| D2 | 73.42 | 76 | 84 |
| D#2 | 77.78 | 72 | 37 |
| E2 | 82.41 | 68 | 20 |
| F2 | 87.31 | 64 | 34 |
| F#2 | 92.50 | 60 | 75 |
| G2 | 98.00 | 57 | 15 |
| G#2 | 103.83 | 53 | 108 |
| A2 | 110.00 | 50 | 96 |
| A#2 | 116.54 | 47 | 107 |
| B2 | 123.47 | 45 | 11 |
| C3 | 130.81 | 42 | 62 |
| C#3 | 138.59 | 40 | 4 |
| D3 | 146.83 | 37 | 91 |
| D#3 | 155.56 | 35 | 68 |
| E3 | 164.81 | 33 | 60 |
| F3 | 174.61 | 31 | 66 |
| F#3 | 185.00 | 29 | 87 |
| G3 | 196.00 | 27 | 121 |
| G#3 | 207.65 | 26 | 39 |
| A3 | 220.00 | 24 | 98 |
| A#3 | 233.08 | 23 | 39 |
| B3 | 246.94 | 21 | 119 |
| C4 | 261.63 | 20 | 80 |
| C#4 | 277.18 | 19 | 51 |
| D4 | 293.66 | 18 | 31 |
| D#4 | 311.13 | 17 | 19 |
| E4 | 329.63 | 16 | 15 |
| F4 | 349.23 | 15 | 19 |
| F#4 | 369.99 | 14 | 29 |
| G4 | 392.00 | 13 | 46 |
| G#4 | 415.30 | 12 | 69 |
| A4 | 440.00 | 11 | 98 |
| A#4 | 466.16 | 11 | 5 |
| B4 | 493.88 | 10 | 45 |
| C5 | 523.25 | 9 | 90 |
| C#5 | 554.37 | 9 | 11 |
| D5 | 587.33 | 8 | 65 |
| D#5 | 622.25 | 7 | 123 |
| E5 | 659.26 | 7 | 57 |
| F5 | 698.46 | 6 | 123 |
| F#5 | 739.99 | 6 | 64 |
| G5 | 783.99 | 6 | 8 |
| G#5 | 830.61 | 5 | 84 |
| A5 | 880.00 | 5 | 34 |
| A#5 | 932.33 | 4 | 116 |
| B5 | 987.77 | 4 | 72 |
| C6 | 1046.50 | 4 | 30 |
| C#6 | 1108.73 | 3 | 119 |
| D6 | 1174.66 | 3 | 82 |
| D#6 | 1244.51 | 3 | 47 |
| E6 | 1318.51 | 3 | 14 |
| F6 | 1396.91 | 2 | 111 |
| F#6 | 1479.98 | 2 | 81 |
| G6 | 1567.98 | 2 | 54 |
| G#6 | 1661.22 | 2 | 27 |
| A6 | 1760.00 | 2 | 3 |
| A#6 | 1864.66 | 1 | 107 |
| B6 | 1975.53 | 1 | 85 |
| C7 | 2093.00 | 1 | 64 |
| C#7 | 2217.46 | 1 | 45 |
| D7 | 2349.32 | 1 | 26 |
| D#7 | 2489.02 | 1 | 9 |
| E7 | 2637.02 | 0 | 120 |
In the clip I’m pinging the flanger (negative feedback, pink noise). Two-octave C major scale demo, DEP=0, played across these DEL/FINE settings:
The same mapping works for positive feedback, but the OT doesn’t behave quite as nicely sometimes producing “squelch” sounds instead.
Have fun!
